Java IO.pdf - Nguyen Dang Binh

Example 15.5. The cat Program
import java.io.*;
class Cat {
}
public static void main (String[] args) {
String thisLine;
// Loop across the arguments.
for (int i=0; i < args.length; i++) {
// Open the file for reading.
try {
BufferedReader br = new BufferedReader(new FileReader(args[i]));
while ((thisLine = br.readLine()) != null) {
System.out.println(thisLine);
} // end while
} // end try
catch (IOException e) {System.err.println("Error: " + e);}
} // end for
} // end main
15.8.3 Line Numbering
Java I/O
The java.io.LineNumberReader class is a subclass of java.io.BufferedReader that
keeps track of which line you're currently reading. It has all the methods of BufferedReader,
including readLine(). It also has methods to get and set the line number. This class replaces
the deprecated java.io.LineNumberInputStream class.
public class LineNumberReader extends BufferedReader
There are two constructors in this class. Both chain this reader to an underlying reader; the
second also sets the size of the buffer.
public LineNumberReader(Reader in)
public LineNumberReader(Reader in, int size)
The LineNumberReader class overrides these six methods from its superclass,
BufferedReader:
public int read() throws IOException
public int read(char[] text, int offset, int length) throws IOException
public long skip(long n) throws IOException
public void mark(int readAheadLimit) throws IOException
public void reset() throws IOException
public String readLine() throws IOException
However, the changes are solely for the purpose of keeping track of the line number. They do
not change the semantics of these methods at all. This class also introduces two methods:
public void setLineNumber(int lineNumber)
public int getLineNumber()
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